1. Field of the Invention
The present invention relates to an external rotor motor for a treadmill, and more particularly, to a motor with an external rotor whose inertia is increased such that it itself serves as flywheel.
2. Description of the Prior Art
As shown in FIGS. 1 and 2, the motor 20 of a conventional treadmill 10 is internal rotor type. The output shaft 22 coupled with the interior rotor 21 has to be provided with a heavy inertia flywheel 23 to drive a driven belt wheel 13 connected with a roller 12 of the walking belt 11 of the treadmill 10 through a driving belt wheel 24 and a transmission belt 25. As a result, the walking belt 11 can perform an in-place rotation for the operator to make a walking or jogging exercise thereon. However, not only increases the inertia flywheel 23 of the conventional interior-rotor motor 20 processing and material cost, but also the dynamic balance thereof has to be treated separately from the interior-rotor motor 20. Accordingly, the required precision is not easily achieved.
It is a primary object of the present invention to provide an external rotor motor for a treadmill, and more particularly, to a motor with an external rotor whose inertia is increased such that it itself serves as flywheel. As a result, processing and material cost can be reduced and the treatment of the dynamic balance is performed only one time. Accordingly, the required precision is easily achieved.